摘要
本文检测了鲱鱼精DNA水溶液经不同时间UV A紫外辐射后的拉曼光谱 ,研究结果表明 ,该区段紫外辐射比用UV A和UV B共同照射对DNA的影响要小 ,主链构象基本稳定。但经较长时间辐射仍会对鲱鱼精DNA造成损伤 ,受影响的部位主要是脱氧核糖和胸腺嘧啶碱基部分 ,UV A对脱氧核糖的影响与UV A加UV B共同照射的结果作比较后 ,可以说明UV A对脱氧核糖的损伤有累积的效应。而对于胸腺嘧啶的影响 ,从其各个指标的分析来看 ,有损伤但程度较小。本实验说明UV A辐射条件下没有嘧啶二聚体的形成 ,也不存在 6 4光产物形成的证明 ,但对于Dewar异构体的形成 ,有部分证明 ,与Taylor(1994)报道的结果相一致 ,UV A没有造成DNA单链断裂现象。
After ultraviolet irradiation of UV-A for 0.5hr. and 15hr,respectively,.Raman spectra of herring sperm DNA in aqueous solution have been reported. The Raman spectral research indicated that the change in the DNA molecule with UV-A irradiation is even less than that with UV-A plus UV-B simultaneity irradiation. The main chain's spatial conformation hardly changed. But the damage of the DNA is increased with a irradiation time elongation,and has been observed at both deoxyribose and thymine. To influence for deoxyribose,compared with the result of UV-A plus UV-B ultraviolet irradiation,it seemed that UV-A ultraviolet radiation had an accumulated effect on the damage of deoxyribose. To influence for thymine,the degree of being damaged is weaken from the present analysis by its different bonds composition,The result have not supported the form of cis-syn cyclobutane-type thymine- thymine dimer,and (6-4) photodimers adducts,but the analysis result of the Dewar valence isomers formed partly have been shown in this work,which is agreed with that reported by Taylor(1994). In addtion,the phenomenon of DNA single chain's break not exist under UV-A radiation condition has been analyses.
出处
《激光生物学报》
CAS
CSCD
2001年第4期306-311,共6页
Acta Laser Biology Sinica
基金
江苏省教委自然科学研究基金 (1998SWX2SJ0 0 0 1)
江苏省生物资源技术重点室基金项目 (编号 :1998SZS0 2 )
